A Preliminary Study of Foraging Habitat Use by Nesting Barn Swallows in Massachusetts

Abstract - Hirundo rustica (Barn Swallow) belongs to a suite of aerial insectivores that are showing serious population declines in northeastern North America. Various causes of these declines have been postulated, especially including agricultural intensification, declining insect populations, and/or increased mortality associated with climate changes. In this study, we examined foraging behavior of Barn Swallows nesting in a large breeding colony located in western Massachusetts. Swallows foraged primarily within 1 km of their nesting site. Most of the nearby agricultural areas used by foraging swallows were broadly characterized as pasture/hay or cultivated land uses; we found no significant difference in foraging activity levels between these habitat categories. In addition to the availability of suitable nesting structures, successful conservation of Barn Swallows likely requires that breeding colonies have access to nearby fields which provide foraging opportunities. Further study is needed to clarify specific habitat management that will enhance populations of flying insects preyed upon by swallows and other aerial insectivores.